Pneumatic door-operating mechanism.



\ P. R. FORMAN.

PNEUMATIO DOOR OPERATING MEGHANISM.

APPLICATION 111.111) SEPT. 21. 1907.

Patented Aug.29, 1911.

Mechanism, of which Umani) STATES PATENT QFFICE.

PARIS R. FORMANOF CHICAGO. ILLINOS. ASSIGNR. BY MESNE ASSIGNMETS. TO i NATIONAL PNEUMATIC COMPANY,y A CURPORATION OIF WEST VIRGINIA.

PNEUMATIC DOOR GPERATING MECHANISM.

Spea'tion 0f Letterslatent i Patented Ang. 29, 1911# Application filed September 2li. 1907. Serial No. 393,908.

To all whom 'it may concern:

Be it known that I, ilaicis 1%. Foiiuax, a citizen of the United States. residing at Chicago, in` the county ot (look.` State of Illinois, have iliade a certain-muv and uselul Invention in Pneumatic Door-t)pei-ating tl|e iollo\vin;r is a specification. i n

This invention reitcs to pneumatic door `o]iieiating mechanism.

The object, oi the invention is to provide means which are simple and cllcient A'or pneumatically cushioning the openingr and closing movi-:ments of doors and similar de vices and to enable the same to come to rest smoothly and easily and without .slain or jar.

A. fnrtherobject.of the invention is to provide means in an apl'iaratus of the class described for securing the ciisliiiiining effect referred to without, the necessity for adjustments after the apparatus is once installed.

Other objects of the invention will appear more fully hereinafter.'

The invention cons ,s substantially in the construction, ci'nnbination, location and.

relative arrangement of parts all as will be more fully hereinafter set forth, as 'shown inthe accompanying drawing, and inally pointed. out in the appended claims.

Referring to Ithe accompanying drawing and to the various views and reference signs appearing thereon, Figure l is a view in top plan soinewh at diagrammatic, showing a pneumatic controlling and cushioningl valve construction embodying the principles ot iny'invention, the valve occupying one of its wide open positions. Fig. E3 is a similar view showing the valve in centered or cutoff position. Fig. 3 is asimilar view sliowing the valve in cushion position. Fig. Ll is anview in elevation showingthe application of acontrolling valve to a door operating mecha- DISIII;

, cylinder` sucnpas` is commonly employed ev'at'or f or; other-'door operating i mecha# main, the supply land exhaustofthe operating fluid to and from each end of the cylinder being controlled by a valve arranged within a valve chamber B. 'In apparatus of this' nature, as heretofore constructed, a.

a very limited movement in either directioin-Iiiist sullicient to open and close the ports. ln accordant-,e with my present invention. however, l prefer to employ a .slidingvalve having a circular motion over `a wat. and the valve extending approximately halt way around andjheld toits seat by the pressure of the operating medium athnitfted to the valve chamber and .sllpcrposed thereon. ly retort-,nce to li`igf-i. l, 2 and i, he .seen thaty the valve chamber s provided with a main pressure .supply port (i, a port inder land a plurality of" exhaust ports, inU

ing of large area and the latter of lii'uited, or restricted area. The exhaust poi-t t) oflarge area should be of sutlicieut area ,t o per# end or the other of the cylinder to which said poi-t may be opened, while the purpose ofthe exhansLpoI-t of limited or restricted 'area is to permit onlya slow exil-l air from the cylinder. These `vaiiol are controlled by a valve 12, which ispl tively actuated, as above explained byi suitf` in Fig. l, all of said ports are uncovered.y This occurs at either extreme limit of mo-` tion of the valve. 4lVhen the valve occupies f a position intermediate its extreme limits of movement however, as seen in Figs. 2 and 3,r only the exhaust port 10i, of small area is i uncovered while the poi-t tlof large area 100 closed. The exhaust port of small area is.` al.;

always uncovered into l'hei'ecess or passage 1 4, whatever the position ofthe valve. From the foregoing description ltvvill be readily `understood Ath'atwyhen the `valve liiifli` inits extreme limitr of` mpvement iin either` direction, v'one or the other of the ends ofA` the cylinder is freely open ,-to the supply of operating medium, while the opposite end' of thecylinder iS f reely` epenedftowexhaust. 110

plane circular seat, the valve stem being` placed at thil axial center ot the valve and its i slide valve is enn'iloyed \vliich.is given onlyy a wiii 7, leading,r to one 4end of the cylinder A, an, port 8, leading to the other endof said cyly this instancetwo9 and 10, the former bemit of the rapid exhaust of the air :from one ust of fsa with the 'exhaustpoi'tsa as seen', for instance i ably imparting rotative movements to its ci to the cylinder at one end, the exhaust from..

the opposite end ofthe cylinder can only be cli'ccted through the exhaust port of small area, and hence causes the door to move at a decreased speed. This decreased speed of movement of the door continues until the port through which pressure is being supplied to the cylinder is closed which causes an arrest of the movement of the door, and smce the slow linal movement of the door 1s `against. the resistance ott'ered by a limited areaof exhaust opening. it is evident that the final arrest of the door movementisj4 without shock or jar or .slam due to lnomentum or otherwise, the door coming to resteasily and smoothly. l'hus it. will be seen that in starting up the door begins its n1ovement quickly and then by the proper 1nanipulation of the valve Ithe movement of the 'door is slowed down, and finally the door is brought to rest easily and smoothly.

'Lhe manipulation of the valve to accomlish the objects and purposes above noted c may be etl'ected in many different ways. In

practice, however, I prefer to operate the /valve manually to position to inaugurate the movement of thedoor, and thereafter, to

' cause the movement of the door or of the door moving means to move thc valve alitomatically to etl'cct the slowing down, or cushioning. Many specifically different construetions and arrangements for accomplishing this result may be employed, the important feature being to close the main exhaust port leaving open only the'port of limited area, and providing ample valve movementso that any reasonableamount of/variation in such movement will not in the least affect the amount of exhaust opening. Herein lies` an important and valuable feature of my invention, since, thereby, it is unnecessary to provide for readjustment of parts after the installation is once I nade, in order to vsecure the desired results, whereas, in former constructions where the cushioning effect is obtained by. partially closing the ports the slightest variation in the amountlof motion given to the valve causes a corresponding variation in 'the' amount of port opening and eonseqiwntly a variation in the cushioning eli'eet, and as such variation in valve moveliu-nt. may readily occur by wear of the valve moving mechanism constant care and attention and readjustment are necessary in 'order to secure uniform cushioning results.

In the particular form of mechanism shown for effecting the manual and the automatic operations of the valve, but to which my'in-vention is in no wise to be limited or restricted a rocking lever :20, is pivotally mounted at one end, as at 21, upon the casting 22, which carries the toothed gear 28,. meshing with rack 9T which is operated by the motor. The other end of this lever 20, is suitablyl connected b v link, rod or other means 23,-with a crank arm 24, on the valve stem 13. Atlso connected to the free end of lever 20, is a rod, link or other suitable con-l nection :25, adaptedv to be operated by a hand lever 0r control handle 26. The rack 2T, operated by the motor and connected to the cross head 2:2, operates the toothed gear 28, to which is`connected the door o erating arln 29. The lever Q0 is formed wit i an enlarged cam-'shaped opening therethrough in which operates a pin 40 carried by the rocking door level' operating gear.

'lhe operation is as follows In order to inaugurate the movement of the door thehand lever or control handle 2G is lnanipulated, therebyirmrking lever Q0, about the point. 21 as a fulcrum and, hence, through the connection 23, displacing the valve` 12, in the proper direction and extent to open one end of the cylinder to pressure supply and the other end-freely to exhaust. Thereupon the motor starts u and the door is moved rapidly. The rocking movement thus imparted to the toothed gear 28 causes the pinillO to ride upon the cam surface of the ,opening formed in level' 20, thereby rocking said level-20 in a direction opposite to that in which the said lever had previously been rocked by the hand lever or control handle. thereby returning the valve a suicient distance toward its centered or cut-ott position to closethe large exhaust port. The closing of the large exhaust opening results in slow-ing down the movement of the door, and enabling the same to be finally brought to rest easily and smoothly.

'hile I have described my inventienas applied `to operating and cushioning the movements of doors it is understood that I am not to be limited or restricted in this regard andmyl invention is equally well adapted for use in many other situations, purposes and uses. Having now set forth the object. andv na. turc of my invention and a construction embodying the principles thereof, what I claim as new and useful and of' my own invention and desire to secure by Letters Patent is:

-1. In a pneumatic door operating mechanism, a motor, a valve cham er having ports respectively communicating .with a source of pressure Vsupply and with opposite sides of the motor, and also havinganexhaust opening, a valve for controlling sid ports,- said valve having a. recess to constantly register with a portion of the exhaust"epen ing, Suid recess being enlarged at its 35 supply o pressure, and on the ,other side to tremities to embrace all of the exhaust openin means for moving the valve to uncover al? the exhaust opening to start the motor, door operating connections actuated by the motor, and means also operated by the .mo-

tor, for returning the valve to position to cover a portion of the exhaust.

2. In a pneumatic door o eratin mechanism, a motor, a valve cham er having ports respectively communicating with a source of pressure supply, and. with opposite` sides of the motor, and also having an exhaust openin a valve for controlling said ports, said va ve arranged, when at the limit of itsl movement, in either direction, to open complete communication between a motor4 port and the exhaust port, and to open the other motor port fully to pressure suppl whereby one side of the motor is openedY to ressure supply and the other side to ful ex( 4 haust, means for moving the valve to the haust without substantially afecting-the limits of its movement, means operated by the motor for moving the valve in rfeverse direction, means whereby the reverse movement of the valve reduces -the area of expressure supply, as the motor approaches the limit-of its action, and door moving devices actuated by said motor.

3. The combination,1 in a pneumatic door operating mechanism, of a motor, a valve Varranged to control the supply of pressure medium to and its exhaust from, saidmotor, means for shifting the valve into position to o en the motor on one side to full `of pressure Vsupply and with opposite sides i of the motor, and also having an exhaust opening, a valve for controlling said ports, saidv valve having a recess to embrace Within its length a motor port and the full exhaust, means for moving the valve into position for the recess therein to embrace a motor port and full exhaust, to start the motorypdoor operating connections 'actuated by the motor, and means also operated b the motor forreturning the valve to osition to r uce the area of exhaust wit out substantially reducing the area of pressure lsupply.

5. The combination, in a pneumatic door operating" mechanism, of a power cylinder, a piston operating therein, a valve cham' ber having ports res ectively communicating with a source o pressure supply and 'vith the cylinder on opposite sides of` said `piston, said `chamber also having a large, exhaust port and a small exhaust port, a,I

valve for controllin said cylinder' and ex- 70 haust ports, means or moving the valve to openthe cylinder on one side of the piston,` 5to ull pressure supply, and on the other -side to full exhaust to start the motor,-

means oper ted by the motor as the piston approaches the limit of its stroke for moving thervalve into position to close the large exhaust port wit-hout closin the small one and without substantially a ecting the full pressure supply, and door moving devices S0 actuated by said piston, v

6.V The combination, in apneumatic door operating mechanism, of af'pow'er cylinder, a pistonoperating therein, a valve chamber' havingf ports respectively communicating 8.a

with a'source-of pressure supply and with the cylinder on`opposite sides` of said-piston, said chamber also having aplurality of exhaust portsyarvalve forcontrolling said cylin der-an-d'xhaust ports, means for moving 90 the valga toy open the cylinder on one side of the piston to full pressure supply, and on the other side to -full `exhaust' through all of the exhaust ports, to start the motor,

means operated by the motor, as the piston approaches' the limit of its' stroke fo'r moving the valve into -position .`to close a' por-V tion of the exhaust ports Vwithout substantially aecting the full pressure supply, and Y actuated by said pisldoor moving devices ton. y y

In 'testimony whereof Irl-rave hereunto set my hand in the presence ofi the subscribing witnesses, on' this ninth day of September A. D.,41907. i

PARIS R.v FORMAN.

Witnesses: i FRANK, J cruisen,

L. M. SHInLDs. 

